<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <!-- 最新版本的 Bootstrap 核心 CSS 文件 -->
    <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/3.4.1/css/bootstrap.min.css"
        integrity="sha384-HSMxcRTRxnN+Bdg0JdbxYKrThecOKuH5zCYotlSAcp1+c8xmyTe9GYg1l9a69psu" crossorigin="anonymous">

    <!-- 可选的 Bootstrap 主题文件（一般不用引入） -->
    <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/3.4.1/css/bootstrap-theme.min.css"
        integrity="sha384-6pzBo3FDv/PJ8r2KRkGHifhEocL+1X2rVCTTkUfGk7/0pbek5mMa1upzvWbrUbOZ" crossorigin="anonymous">

    <script src="http://code.jquery.com/jquery-2.1.1.min.js"></script>
    <!-- 最新的 Bootstrap 核心 JavaScript 文件 -->
    <script src="https://stackpath.bootstrapcdn.com/bootstrap/3.4.1/js/bootstrap.min.js"
        integrity="sha384-aJ21OjlMXNL5UyIl/XNwTMqvzeRMZH2w8c5cRVpzpU8Y5bApTppSuUkhZXN0VxHd"
        crossorigin="anonymous"></script>
    <style>

    </style>    
</head>

<body>
    <div class='container'>
       
          <!-- <div class="row" style="background-color: cyan;">
            <div class="col-xs-12 col-sm-4 col-md-6" style='background-color: cornsilk;'>
                <div class="col-xs-12 col-sm-4 col-md-6">
                         我是内容1
                </div>
                <div class="col-xs-12 col-sm-4 col-md-6">
                         我是内容2
                </div>          
            </div>
            <div class="col-xs-6 col-sm-4 col-md-4  col-sm-offset-4 col-md-offset-4" style="background-color: pink">
            </div>
          </div>
          <div class="row" style="background-color: darkgrey;">
            <div class="col-xs-6 col-sm-4">.col-xs-6 .col-sm-4</div>
            <div class="col-xs-6 col-sm-4">.col-xs-6 .col-sm-4</div>
            Optional: clear the XS cols if their content doesn't match in height -->
            <!-- <div class="clearfix visible-xs-block"></div>
            <div class="col-xs-6 col-sm-4">.col-xs-6 .col-sm-4</div>
          </div> -->
          <div class="row">
            <div class="col-md-9 col-md-push-3">1111111111111111111</div>
            <div class="col-md-3 col-md-pull-9">2222222222222222222</div>
          </div>
    </div>

</body>

</html>